Haven't seen it under $4300 as of current offer.
I just sold my 861 for 4500.But I must say you should consider other players. The Wadia is sterile and uninvolving.Transparent alwright but no life, it wont draw you into the music has much as say a Accuphase. I bought a Accuphase pd65v, much better player,sweet sweet sweet, soundstage is layered and as wide has your speakers can dish out.
There are other players to consider abouve the wadia, audio areo capital for 4500. 2 are for sell now for that price.
My 2cents worth YMMV
Without sounding flippant, I'd say the best price is the lowest offer that a seller accepts. Lowest price for an 861 I've seen advertised on AGon is $4300. I have one for sale myself at a higher price. Depends on condition, age, feedback on seller, etc. My recommendation is to find someone who has the unit you want (830, 831, 860, 860x, 861, 27ix, etc.) and make them an offer. Only thing they can do is say no.
RE: Steve's comments. I currently own, and am selling both, the 861 and the Accuphase 75V. Mileage varies, but I would never characterize the 861 as "sterile and uninvolivng". I have heard this rig in many setups, and it can sound fabulous. Steve is correct that Accuphase has more "euphonincs" and sounds a little closer to analog, but the Wadia has a sense of quiet and background that can be spooky. Both are reference players, which cater to a different type of sound.
Best of luck in your search. Wadia makes great products.